Arrangement for starting internal combustion engines



Oct. 16, 1956 w. STEGEMANN 2,766,749

ARRANGEMENT FOR STARTING INTERNAL COMBUSTION ENGINES Filed Oct. 14, 1953INVENTOR M r/zers/eyemaz/n;

ARRANGEMENT FOR STARTING INTERNAL CUMBUSTION ENGINES Werner Stegemann,Pinneberg, Germany, assignor to Heinrich Ch. Christiansen, Wedel,Germany Application October 14, 1953, Serial No. 385,994

Claims priority, application Germany October 16, 1952 7 Claims. ((31.123-179) Internal combustion engines and especially engines designed fordriving vehicles are generally started by electrical power furnished bya battery. For starting vehicle and aircraft motors of higher power, e.g. in excess of 100 H. P., very large batteries are necessary forfurnishing the desired energy since high internal resistance has to beovercome. Low temperatures increase the ditficulties encountered instarting the respective engine since the internal resistance increasesto a considerable extent due to the lubricating medium beingparticularly viscous at those low temperatures. Furthermore, severe coldreduces the efficiency of an electrical battery to a fraction of what itis at normal temperatures. Therefore, large vehicle and aircraft motorshave already been started by means of a small internal combustionengine, especially by a gasoline engine. In this connection it isexpedient prior to the starting of the main motor to heat the same byhot water which is passed through the cylinder cooling jacket to therebyfacilitate the cranking of the engine and to prevent corrosion damagesdue to low cylinder temperatures. The said preheating may generally beeffected by any device which warms or evaporates the water and must beheated by a flame; this is rather cumbersome, causes a loss of time, andrepresents a fire hazard.

In order to overcome these drawbacks, I have invented a new and usefuldevice for the starting of internal combustion engines which deviceelfects both the pre-heating as well as the cranking of such engines.The device according to my invention principally comprises an auxiliarymotor which may be coupled with the main motor or main engine and a pumpcirculating the cooling medium of the main engine, the pump being drivenby the auxiliary motor and having an internal resistance of such amagnitude as to heat or warm the cooling medium. For the purpose ofstarting the main motor, the device according to my invention isoperated in such a manner that the auxiliary motor at first drives butthe pump which exercises now two functions namely the one function ofcirculating the cooling medium and the other function of increasing thetemperature of that medium owing to the internal resistance of the pumpitself. As a result of this double function, heat is conveyed to thecylinders of the main engine by means of the warmed up or heated coolingmedium. After having sufiiciently prewarmed or pre-heated the mainengine in this way within a short time, the auxiliary motor is coupledto the main engine thereby cranking the same in a manner known per se.

It is a further object of my invention so to form and to dimension thecirculating pump as to cause the latter to absorb and to consume thefull output of the auxiliary motor at the rated speed of said auxiliarymotor. Since the power required for merely circulating the coolingmedium is very small compared with the power required for cranking themain engine, most of the power of the auxiliary motor may be used forwarming up or heating Patented Oct. 16, 1956 the cooling medium and forspeeding up the process of warming up or heating the main engineaccordingly. In order to transform this major portion of the outputpower of the auxiliary motor within the circulating pump into heat to betaken up by the cooling medium, I design the pump so that the latterwill have a correspondingly high flow resistance. As a result thereof,the pump first of all produces heat by liquid friction and circulatesthe warmed or heated cooling medium by means of the rest of the receivedpower, thus rapidly increasing the temperature of the cooling medium andquickly warming up the main engine. Preferably, I design the said pumpas a brake of the water whirling type.

Further objects and advantages of my invention will appear more clearlyfrom the following specification in connection with the accompanyingdrawings, in which:

Fig. 1 diagrammatically illustrates a side elevation of an arrangementaccording to the invention.

Fig. 2 shows on a somewhat larger scale a vertical axial section througha part of the arrangement, namely the above mentioned circulating pump.

The arrangement shown in Fig. 1 comprises an internal combustion engine1 henceforth called the main motor, with a crank shaft 2, and a coolingjacket 3 for the motor cylinders. An auxiliary motor 4in this examplelikewise an internal combustion engine-drives a circulating pump 5 andis coupled with a fiy-wheel 6 of a relatively large capacity of storingup kinetic energy; via a step-down transmission 7 and a shiftable clutch8, the auxiliary motor 4 is adapted to crank the crank-shaft 2 of themain motor. The pressure conduit 9 of the pump 5 leads to the coolingmantles 3 of the main motor, if desired via the cooling jackets it ofthe auxiliary motor 4. The reference numeral 11 designates the pipereturning the cooling medium to the pump 5.

As shown in Fig. 2, instead of having its periphery provided withblades, the rotor 12 of the circulating pump is provided with edged orround pins 13 rotating similar to a water whirling brakein the narrowspaces of equal pins 14 situated in the pump housing and therebycreating a strong turbulence which will absorb the larger portion of thedriving power and transform it into heat thus resulting in a rapidincrease of the cooling medium being circulated.

The actual starting process, i. e. the starting of the main motor iseffected by throwing in the clutch 8 after the auxiliary motor 4 hassuificiently warmed up the main motor by circulating the cooling mediumand while the auxiliary motor is still rotating at high speed. In thisway, the stored up kinetic energy of the fly wheel 6 which likewiserotates at high speed, is taken advantage of to start rotation of themain motor. This effect is still further assisted by the torque inexcess of the torque required by the whirling brake, which increasesrapidly with the decreasing number of revolutions.

In addition to passing the cooling medium through the cooling jacket ofthe main motor, and, if desired, through the cooling jacket of theauxiliary motor, the cooling medium may suitably be passed through acooling housing surrounding the pipe and the muffler of the auxiliarymotor in order to make full use of the total waste heat of the auxiliarymotor for warming up the main motor.

A further advantage of the coupling of the auxiliary motor with thecombined circulating pump and the whirl brake consists in that theotherwise indispensable speed governor or speed limiting device for thestarter motor can be omitted since due to the characteristic graph ofthe torque of rotation of the whirl brake, said torque increasing withthe second power of the number of revolutions, a racing of the auxiliarymotor will be safely prevented.

In order to store a maximum amount of kinetic energy in the fly wheel 6,it is advisable, when using a relatively small auxiliary motor of lowoutput to increase the number of revolutions of the fly wheel 6 inexcess of the limit caused by the whirl brake effect of pump 5. Besidesit may be desirable to accelerate the fly wheel to quite a high numberof revolutions within the shortest possible time. For this purpose,according to the invention, either a shiftable coupling 15 may beprovided between the auxiliary motor 4 and the pump 5, or it may bepossible by suitably placed valves and vents to empty the pump 5, whichacts as whirl brake during the starting process proper so that pump doesnot act as a load to the auxiliary motor 4 when the main motor is beingstarted.

In the state of operation after having been started, the main motor 1works with its ordinary cooling system, c. g. with a cooling mediumcircuit in which its cylinder jackets 3 are connected to an air cooler18 by pipes 16 and 17. At the branch points or mouths of the pipes 16and 17 are respectively arranged valves 19 and 20; in such a case thevalve 20 may be designed for simultaneously venting the pump 5 whenemptying it.

I claim:

1. In combination with a water-jacketed internal combustion enginehaving a crank shaft and a starting engine for cranking said crankshaft: an energy converter operable in the manner of a liquid frictionbrake drivingly connected to said starting engine, conduit meansconnecting said energy converter with the water jacket of said internalcombustion engine, said energy converter being operable to convert andconvey at least the major portion of the energy output of said startingengine as heat to the cooling water for said internal combustion engine,energy storing means drivingly connected to said starting engine, andshiftable clutch means arranged between said starting engine and saidcrank shaft and operable selectively to effect or interrupt drivingconnection between said starting engine and said internal combustionengine.

2. An arrangement according to claim 1, in which said energy converteris so dimensioned as to take up the full output of said starting engineat the rated speed thereof.

3. In combination with a water-jacketed internal combustion enginehaving a crank shaft, and a water-cooled starting engine for crankingsaid crank shaft: an energy converter operable in the manner of a liquidfriction brake, conduit means connecting said energy converter with thewater jacket of said internal combustion engine, said energy converterbeing operable to convert and convey at least the major portion of theenergy output of said starting engine as heat to the cooling water forsaid internal combustion engine, energy storing means drivinglyconnected to said starting engine, cooling circuit means for saidstarting engine, at least a portion of said cooling circuit means beingconnected to said conduit means, and shiftable clutch means arrangedbetween said starting engine and said crank shaft and operableselectively to effect or interrupt driving connection between saidstarting engine and said internal combustion engine.

4. In combination with a water-jacketed internal combustion enginehaving a crank shaft, and a water-jacketed starting engine for crankingsaid crank shaft: conduit means interconnecting the water jackets ofsaid engines and representing a closed cooling circuit for the jacketsof said engines, an energy converter arranged in said cooling circuitbetween the water jacket outlet of said internal combustion engine andthe water jacket inlet of said starting engine, said energy converterbeing operable simultaneously as liquid brake and pump so asfrictionally to heat the water passing through said energy converter andto convey the heated up water to said water-jacketed internal combustionengine, energy storing means drivingly connected to said startingengine, and shiftable clutch means arranged between said starting engineand said crank shaft and operable selectively to effect or interruptdriving connection between said starting engine and said internalcombustion engine.

5. In combination with a water-jacketed internal combustion enginehaving a crank shaft and a starting engine for cranking said crankshaft: an energy converter operable in the manner of a liquid frictionbrake drivingly connected to said starting engine, conduit meansconnecting said energy converter with the water jacket of said internalcombustion engine, said energy converter being operable to convert andconvey at least the major portion of the energy output of said startingengine as heat to the cooling water for said internal combustion engine,shiftable clutch means interposed between said starting engine and saidenergy converter for selectively effecting or interrupting drivingconnection of said energy converter with said starting engine, energystoring means drivingly connected to said starting engine, and shiftableclutch means arranged between said starting engine and said crank shaftand operable selectively to effect or interrupt driving connectionbetween said starting engine and said internal combustion engine.

6. In combination with a water-jacketed internal combustion enginehaving a crank shaft and a starting engine for cranking said crankshaft: an energy converter operable in the manner of a liquid frictionbrake and drivingly connected to said starting engine, conduit meansconnecting said energy converter with the water jacket of said internalcombustion engine, said energy converter being operable to convert andconvey at least the major portion of the energy output of said startingengine as heat to the cooling water for said internal combustion engine,by-pass conduit means including radiator means arranged selectively tobe connected with the cooling circuit for said internal combustionengine while by-passing said energy converter to thereby allowcirculation of cooling Water through the jacket of said internalcombustion engine without passing said cooling water through said energyconverter, energy StOringmeans drivingly connected to said startingengine, and shiftable clutch means arranged between said starting engineand said crank shaft and operable selectively to efiect or interruptdriving connection between said starting engine and said internalcombustion engine.

7. An arrangement according to claim 1, in which said energy converteris provided with a discharging valve for draining said converter.

References Cited in the file of this patent UNITED STATES PATENTS1,356,065 Heinze Oct. 19, 1920 1,598,289 Lee Sept. 14, 1925 2,228,098Vaupel Jan. 7, 1941 FOREIGN PATENTS 134,605 Great Britain Mar. 1, 1919

